Calculator.



F. S. BEGKETT-.

CALCULATOR.

APPLICATION FILED SEPT. 6, 1910.

Patented Oct. 29, 1912.

UNITED s x'rns PAT QFFICE.

. FRANKLIN S. BECKETT, OF BERKELEY, CALIFORNIA.

CALCULATOR.

Specification of Letters Patent.

PatentedOct. 29,1912.

Application filed September 6, 1910. Serial No. 580,774.

To all whom it may concern Be it known that I, FRANKLIN S. BECKETT,

citizen of thewUnited States, residing at Berkeley, in the county of Alameda and 'Stateof California, have invented new and useful Improvements in Calculators, of

which the following is a'specification.

My invention relates to a device for mechanically multiplying and dividing, and computing roots and powers of numbers.

The ob ect of this invention is to provide I a simple, practical device whereby the anin which a maximum. length of scale .is ob-' swer of mathematical problems maybe determined mechanically with a minimum ex ercise of the mental faculties.

further object is to provide a calculato tained in a minimum space so that the gradnations or divisions are relatively large with relation to the size of the device itself where I by the accuracy of, the com utation is increased. This object is obtained primarily by the use of a spiral scale.

Another object is the provision of means for determining the decimal point as 'calculation proceeds, all as will be hereinafter more'fully described.

The invention consists of the parts and the construction and combination of parts as and. claimed, having reference to the accompanyhereinafter more fully I described ing drawings, in which-- Figure 1 is a plan view of the invention. Fig. 2 is a side elevation partly broken away. I h

In the practical embodiment of the invention represented in the drawings, A is a fixed disk having a continuous, logarithmic scale' 2.

B is a radial disk spaced from, and ar-- ranged above, and of lesser diameter than,

disk A and carrying two parallel, spirally arranged, log-log scales 34; which. scales bear the same relation to the log scale 2 thatthe latter does to the natural scale. In other words, the scales 34 are the log of the logarithmic scale 2; thescale4 be-- ing the reciprocal of sale 3. Scales 3-4 .are spaced from one another by a spiral' dividing line 5. The outside scale 3 is graduated from its inner end outward logarithmically from 1.0 to 10,000,000,000. The

inner scale 4, is graduated from 1.0 from its inner end outwardly to .O00,000,000,1.

. The outside scale 3 is used for roots and a powers greater than Land the inside spiral .with other 'auxiliary sight lines 7 the function of which will be shown later.

D is a transparent, radial pointer, having a radial sight line 8, which is pivoted on the stud or post 9 which latter extends centrally through all the disks. Thispointer D is turnable over the surface of the trans- .parent disk C, audit is by means of this point-er with its radial sight line 8 in conjunction with the fixed sight line 6 and the scales 23-4 that all problems involving the computation of roots and powers are solved.

In practice, to find a power--First Place' themovable pointer D with its sight line 8 to the required power shown on the fixed,

logarithmic scale 2. Second: Rotate spiral scale disk B until the fixed sight line 6 cuts the number whose power is to be determined. Third: Read the answer on the spiral scale cutby' the movable sight line 8.

Thus, for example, if 4 is to be raised to the second power, move the pointer so that the radial sight line 8 points to 2 (the power) on the fixed, logarithmic scale 2. Then rotate the spiral scale until thefixed sight line 6 cuts the number 4:. The answer 16 will show on the spiral scale underneath the radial sight line 8. To determine the roots of numbers, the operation is reversed;

the fixed, logarithmic scale 2 representing the vincula of all numbers. The root shows on the spiral under fixed sight line 8. Thus, it will be seen that the fixed logarithmic scale'represents the exponents and vincula of all numbers, and the spiral indicator the powers and roots and the numbers or prodnets of the powers and roots.

The auxiliary, fixed sight lines 7 previously referred to are simply for easy discernment of the most ordinary powers and roots, like two, three, four and five. 1

For the purpose of multiplication and division there is used in conjunction with the fixed disk A with its logarithmic scale 2 a larger and lowerrotatab'le disk E' which has two com-eutrie. logarithmic scales --'ll; the scale 10 progressing to the rightand used for ll'lllltll)ll(flll0ll. and the inner scale iro 'ressin to the left and being used and left over the lixed scales 14-45 of the Ill":

. till base 16. Scale 14 extends to the right from zero upward and is used when multiplying by 10 or a number greater than 10; and for dividing by a number less than one.v St'ill 15 extends from zero to the left progressively and is used when dividing by 10 or a number greater than 10: or multiplying by a number less than one. The beginning 1.0 of the two scales 1011 represents a neutral point.

In operation to multiply x4-:First: The decimal point moved one space to the right on the scale H by the'decimal gage G, so that. the line 13 extends over the numeral of-thc scale 14, and reduces 50 to 5.0.

Second: Rotate gage F until sight. line 12 cuts 'muliiplicand' 50.( 5.0l on fixed log scale 2. Third: Rotate disk E carrying scales 1011 until its neutral point 1.0 is cut by sight line 12 on F. Fourth: Thenrotate gage F to the rightuntil its sight line 12 cuts the multiplier t on multiplying scale 10; but each time gage F passes zero on scales 1et-17yto the right the gage G, is moved an extra point to the right so that this now brings line 13 on over 2 on scale 14. Fifth: Read the product which will be the number appearing on the fixed scale 2 underneath the sight line 12. which product will appearas 2.0, but the decimal indicator shows that the decimal point is to be moved two points to the right, so that the correct product is 200: -With division, the operation is reversed; the segment F moving to the left and the decimal gage G moving an extra point to the left should segment F pass zero on scales 1415I In order that the several degrees BC and that the degrees BE, pointer D. and segment F(:l may all be moved independent of one another and anyone of them moved without disturbing the others, I prefer to mount the several disk members on the post 9 in the following manner: This post is fixed in the base 16, Fig. 2, and carries a series of spaced, non-rotating washers 17. The rotatable parts G-EB D have large perforations fitting over the washers 17 and loosely revolving about these washers 17 as hubs, and between the washers are clamped the stationary disks A-C, and any necessary fixed fillers, as 18. The thickness of the rotatable parts GEBD is less than the thickness of the washers so that the parts can be easily turned.

Having thus described my inventiomwh at I claim and desire. to secure by Letters Patent is- 1 A calculator having in combination a pair of superposed disks, the upper one of less diameter than. the lower, and a central axis eommonto both, the lower disk being revoluble and having two concentric logarithms. one progressing in one direction and the other in the opposite direction. the upper disk being stationary and provided with an annular logarithmic scale, and a decimal indicator in conjunction with the lowermost of said disks.

A calculator having in combination a pair of superposed disks, the upper of less diameter than the lower, and a central axis common to both the lower disk being revolnble and having two concentric, logarithmic s'calesfone progressing in one direction and the other in the opposite direction, the upper disk being stationary and provided with a. logarithmic scale, a radial sight line movable over the scales on the disks, oppositely extending scales arranged in mathematical progression, and a decimal indicator in conjunction with the lowermost of said disks said decimal indicator including a radial sight line movable right and left over said oppositely extending scales.

A calculator comprising in combination a suitable base and a vertical stud extending tlu-re'l'roni. a series of superposed, movable and fixed disk members concentric with the stud, washers fitting the stud and in the plane of the movable disks and about which the movable disks turn. said washers being slightly thicker than the movable disks and operative to hold the fixed disks clampfashion in stationaryposition.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

FRANKLIN S. BECKETT.

Witnesses:

CHARLES EDELMAN, CHARLES A. PENFIELD. 

